My understanding is that you have to weld acording to your thinnist piece, yea your welding to half in. tube but how thick is the truss..... Another trick I have learned is to dirrect your heat more towards the thicker piece, that way your thicker piece gets more heat and more penetration (which it can handle) and the thinner piece still gets penetrated... Oh crap theirs got to be a better word for that? Oh well get your minds out of the gutter... LOL
